Numerous techniques have been developed to provide special effects in film and captured digital footage and other forms of visual media through the manipulation of physical light sources to alter the manner in which the light from such sources impinge upon various objects or persons in a scene. By altering the position from which the light from a light source is directed upon a subject during filming or digital capture, various desirable artistic effects may be achieved that can enhance viewing enjoyment during playback.
These techniques have often heretofore involved placing continuous light sources on tracks or vehicles, and more recently robotic arms, by their physical location may be altered during filming or digital capture. Known techniques are limited by a number of factors. First, continuous light sources that provide sufficient illumination to achieve are typically in the 10,000 to 20,000 watt range. As such, they are very large and heavy, making it very difficult to move them over any significant distance and with the speed required by high-speed digital cameras employed today.
For example, high-speed filming or digital image capture might be used to capture action that lasts only fractions of a second. Such action is filmed or digitally captured at a frame rate that permits the capture of hundreds to thousands of frames over such a small duration of time, thereby permitting a slow-motion or even “frozen-in-time” presentation of the action during playback at a more typical frame rate. It would be impossible to move a conventional continuous light source around in the fractions of a second that would be required to capture movement of one or more light sources during such a short duration.
Moreover, such techniques are very expensive, cumbersome to coordinate with the filming or digital image capture process, and are limited in their general applicability. For example, it might be desirable to change the shape of the path over which the light source travels from one scene to another, or to create alternate path shapes for a given scene. It might also be useful to move more than one source each over a different path.